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The 3 Keys to Understanding Six Sigma

Once your organization establishes a set framework and operations are running smoothly, maintaining continuous improvement will likely become a priority. And improvement isn't only reserved for profits. It can be achieved in several areas in your company including safety, product quality, cycle time and production cost.

However, the difficult part is implementing a sound strategy that aligns with your goals to improve business operations toward perfection. It is here where Six Sigma comes into play.

What is Six Sigma?

As a management philosophy that intends to optimize your manufacturing operations, Six Sigma uses statistical tools to help you improve the efficiency and quality of your output. The method does this by tracking your data, setting optimistic objectives and analyzing your results to reduce the amount of defects within your operations.

The idea behind Six Sigma is that by being able to identify your defects, you’ll be able to systematically eradicate them so your organization can get closer to perfection. There are three distinct areas of Six Sigma that make the philosophy easier to understand.

The first one deals with the overall philosophy of the strategy.

The Philosophy of Six Sigma

In general, process improvement can take on two different forms. The first is a radical change where operations are totally rearranged, newer technologies may be brought on board and much time is spent adjusting to the new work routine. The second option comes in the form of gradual improvement.

This gradual or incremental change in your organization’s processes works best with Six Sigma as it allows you to see the progress in your operations as opposed to starting from scratch with a radical transformation.

Six Sigma is often compared to Lean Manufacturing — and rightfully so. As Lean labels seven categories of waste (overproduction, excess inventory, over-processing, excess motion, waiting, transportation and defects), Six Sigma aims to identify and eliminate the root cause of the defects.

Statistical Tools

In Six Sigma, there are two processes — DMAIC (define, measure, analyze, improve and control) and SPC. DMAIC is a problem-solving methodology that helps manufacturers approach issues with defects and solves them systematically.

Once a defect is located and defined, a measurement plan is made to accumulate the data necessary to analyze the defect. Once this is done, the process will be adjusted to improve its functionality. And finally, once this process is mastered, these improvements are institutionalized to become the new standard in the process — establishing control.

SPC — or Statistical Process Control — is a tool that is used to measure control. In short, this method uses statistical methods (standard deviation) to monitor the process and ensure that it continues to function well over an extended period of time. More details about the inner workings of this method can be found here.

Quality Measurements

Six Sigma also makes use of standard deviations to display statistical data of a particular process. This method uses mathematics to confidently measure a process’s potential, effectiveness and likelihood of straying away from perfection (variation).

The main objective of Six Sigma is to decrease an organization’s output variation — or in other words — reduce the amount of defects to no more than 3.4 parts per million (PPM). While there will always be variation, the key is to maintain good process control to avoid defects.

For more about the statistical method of measuring defects through standard deviation, what process control and process capability entail, the quality level of different standard deviations and the idea of shift and drift, download our Guide to Six Sigma eBook.

The guide includes helpful graphs, real-world examples and detailed explanation so your organization can get a full, comprehensive grasp on the perfection-driven strategy that is Six Sigma.